Thin layer solar cell modules, also called thin layer photovoltaic modules, have photoactive layers with thicknesses in the range of micrometers. The semiconductor material that is used in the photoactive layer or layers can be amorphous or microcrystalline. A combination of layers of amorphous and microcrystalline semiconductor material within a cell is also possible, for example, with the so-called tandem cells and the so-called triple cells. Possibilities for semiconductor materials are Si and Ge and compound semiconductors like CdTe or Cu(In, Ga)Se2 (abbreviated CIS or CIGS). In spite of a somewhat lower efficiency than layer solar cell modules, because of their clearly lower material requirements, thin layer solar cell modules represent an economical and technically relevant alternative to solar cell modules that are produced on the basis of single-crystal or polycrystalline semiconductor layers of macroscopic thicknesses.
To be able to use economic modules with a surface area that is as high as possible, without the current laterally discharged in the electrodes of the solar cells becoming so great that high ohmic losses arise, thin layer solar cell modules are usually divided into a plurality of segments. The strip shaped segments, which as a rule are a few millimeters to centimeters wide, mostly run parallel to one edge of the module. The segments formed in that individual layer of the layer structure of the solar cell are interrupted by thin separating lines with a continuous substrate. The separating lines lead, for one thing, to like layers of adjacent segments being electrically isolated from each other and, for another, to the fact that subsequently applied layers can be electrically connected to underlying layers along a contact line. With the appropriate arrangement of the separating lines a serial connection of the individual segments can in this way be achieved.
According to the prior art the formation of a separating line takes place in each case immediately after application of the layer. Since the application of layers usually takes place under vacuum conditions, but the formation of the separating lines usually takes place spatially separately under atmospheric conditions, the production process according to the prior art requires a complicated process setup. In addition, with the frequent loading and unloading operations in and out of the vacuum there is the danger of incorporating contaminants between the layers of a solar cell. Material removed during the structure-producing operations that settles on the layers can also be such a contaminant.